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It's more and more common to use LED as the light source in automotive lighting. But heat dissipation and low light output of single die light source have restricted the LED to be the mainstream. To use fiber as light-transmitting component could perfectly resolve above weakness. In the paper a design method of LED fiber automotive headlamp is mentioned. And for COB (chip on board) LED, a mathematic model of TIR (total internal reflected) lens is proposed. It could effectively focus the rays emitted from surface light source.

Background Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the major swine pathogens. This virus causes immune suppression and other secondary infections, leading to significant economic losses in the swine industry. Tea seed saponins (TS) are a natural extract from tea seeds with anti-cancer, anti-inflammatory and antiviral activity. In this study, we demonstrated that TS possessed anti-PRRSV activity.Methods MTT assay and trypan blue staining were used to evaluate the cytotoxicity and antiviral ability of TS in cell culture. Apoptosis was measured to assess the safety of TS on Marc-145 cells. Time-of-addition assay, entry inhibition assay and virucidal assay were used to assess the antiviral action of TS. The effect of TS on host cellular gene expression was analysed by real-time PCR. Absolute quantification RT-PCR and western blot were used to study the inhibitory effect of TS on PRRSV N gene and protein expression.Results Our results showed that 50% cytotoxic concentrations (CC50) and 50% effective concentration (EC50) of TS were 59.86 ±0.3841 µg/ml and 24.29 ±1.194 mg/ml, respectively. The maximum non-cytotoxic concentration of TS on Marc-145 cells was 30 µg/ml. TS inhibited PRRSV-induced cell apoptosis and effectively inhibited PRRSV replication by reducing the expression of host cellular gene PABP, and significantly inhibited virus N gene/ protein expression.Conclusions TS possessed anti-PRRSV activity in vitroand could serve as a potential antiviral drug for PRRSV prevention and control.

Background Our previous studies have demonstrated that sodium tanshinone IIA sulfonate (STS), a natural compound derived from Salviae Miltiorrhizae Radix et Rhizoma(Danshen), could effectively inhibit Marek's disease virus (MDV) infection both in vitroand in vivo, but the underlying mechanisms remain unclear. The main objective of the study was to explore the effect of STS on the meq, ul49and VP22 expression of MDV in vitro.Methods Quantitative real-time PCR (qRT-PCR) was used to analyse the effect of STS on meqand ul49expression at both the DNA and messenger RNA (mRNA) level, and the effect of STS on VP22 was assessed by immunofluorescence assay and western blotting.Results The DNA and mRNA copy numbers of meqand ul49significantly decreased in the groups treated with STS compared with MDV control (P<0.05), which indicated that STS could inhibit the expression of meqand ul49at both the DNA and mRNA level. Moreover, the expression of VP22 encoded by ul49was also significantly inhibited (P<0.05).Conclusions STS possessed anti-MDV activity in chicken embryo fibroblasts. Its antiviral mechanisms may be ascribed to inactivating MDV directly, disturbing meqand ul49replication and inhibiting the expression of VP22 encoded by ul49. These results suggested that STS is a promising natural compound to be further developed as an antiviral agent against MDV infection.

Zr45.1Cu42.3Al8.7Si1.4Y2.5 (at. %) metallic glass alloy was prepared by using copper mould casting. The crystallization behaviors of the alloy during continuous heating are investigated mainly by differential canning calorimeter (DSC). The activation energies were obtained from the Kissinger and Doyle equations. The results show that the activation energies of glass transition (Eg), crystallization (Ex) and peak crystallization (Ep) are 365kJ/mol, 281 kJ/mol and 279 kJ/mol, respectively. The crystallization activation energies are all less than the corresponding data of ZrCuAlSi alloy, the results show that thermal stability was decreased with the Y addition.

Copper matrix composites with different La2O3 content were fabricated by powder metallurgy method. Sliding wear behavior of the Cu-La2O3 composites was carried out by using a pin-on-disk wear tester under dry sliding conditions at a constant sliding speed of 20 m/s. The results showed that the wear rate of the composites was significantly lower than that of pure copper. The friction coefficient and wear rate of Cu matrix composites decreased significantly by incorporation of La2O3 particles. For determination of the wear mechanisms of the composites, the worn surfaces were examined using scanning electron microscopy. It is found that the main wear mechanisms of the sintered copper-La2O3 composites were oxidation wear and adhesive wear.

Copper matrix composites with 3wt% diamond particles were fabricated by powder metallurgy method. Sliding wear behavior of the copper-diamond composites was carried out by using a pin-on-disk wear tester under dry sliding conditions at a constant sliding speed of 100 m/s. The results showed that the wear rate of the composites was significantly lower than that of pure copper. The addition of diamond particles can markedly increase hardness and wear resistance of the copper-diamond composites. For determination of the wear mechanisms of the copper-diamond composites, a scanning electron microscope (SEM) equipped with energy dispersive spectroscopy (EDS) was employed to observe the microstructure and analyze the chemical compositions of the worn surface. It is found that the main wear mechanisms of the sintered copper-diamond composites were abrasive wear and adhesive wear.

Amorphous Fe-17 at %B alloy prepared by a splat-quenching technique was annealed at temperatures ranging from 250 to 500° C for different periods. A time-temperature transformation diagram has been constructed from X-ray diffraction examination of annealed samples. On annealing the alloy at a pressure of 50 kbar, an appreciable retardation of crystallization was observed. The crystalline phase precipitated first from the amorphous matrix at 1 bar. This was a-Fe containing a small amount of boron, but at 50 kbar this was a mixture of a-Fe(B) and intermetallic phase Fe3B. Under the increased pressure of 100 kbar the mode of the crystallization was further changed and Fe3B became the first precipitating phase. Preferential formation of Fe3B under pressure can be explained assuming a modified dense-random packing model for the amorphous structure.